09/27/2011 06:54 EDT | Updated 11/27/2011 05:12 EST

Mallett asks why can't Italy rely on its strengths if the All Blacks' pretty play is praised?

NELSON, New Zealand - Italy coach Nick Mallett gets exasperated at claims his team is too reliant on its front row and scrummaging, arguing that a strategy of playing to your strengths at the Rugby World Cup shouldn't need to be defended.

The Italians completely overwhelmed the U.S. Eagles' scrum in the 27-10 win in Pool C at Trafalgar Park on Tuesday, winning a large majority of their 19 penalties from setpiece infringements as their opponents were shunted back time and time again.

American blindside flanker Louis Stanfill was sent to the sinbin in the 59th after the referee's patience eventually ran out, allowing the dominant Italy scrum to win a penalty try eight minutes later to secure a bonus point that could prove crucial in Sunday's crunch match against Ireland.

"There was no reason why we shouldn't destroy America's scrum today," Mallett said. "It's frustrating for me a little bit when sometimes the team gets criticized. But no one criticizes the All Blacks for playing with their backs, for scoring great tries because they've got some of the most skilful backs in the world.

"If Italy is sitting with probably one of the best front rows in the world, it would be really ridiculous not to use that strength. I think we got between 10 and 12 penalties from scrum offences in the game today, and we got a penalty try. Clearly, we had a very dominant scrum."

The Americans may have been outmatched at scrum time but they excelled in the loose, competing equally at the breakdown and carrying the ball over the advantage line around the ruck. Loosehead prop Mike MacDonald's charges, in particular, made an impression on Mallett.

"That No. 1 prop was all over the field — he never stops running," Mallett said. "It's much better for him to have his head ... in the scrum and getting scrummed than running around the field causing trouble for us."

Mallett had wanted to replace star tighthead prop Martin Castrogiovanni and captain Sergio Parisse with 20 minutes left with the Ireland match in mind. But he had to leave his No. 8 on the pitch for the full 80 minutes and Castrogiovanni only came off eight minutes before fulltime.

Parisse was full of praise for the U.S. performance and wasn't surprised he was required to play the full match.

"They showed a lot of physicality, a lot of heart, in all their matches at this World Cup," he said. "We expected a really tough game and we got one."

Mallett defended his substitution tactics, noting that the bonus point means Italy can afford to beat Ireland by less than eight points and still advance to the quarterfinals, providing his players don't concede four tries.

"We needed to get that penalty try, we needed to get that extra point," Mallett said. "I would have preferred to take players off earlier but in the end it worked out OK because we didn't get any injuries and we're going to really look after the guys over the next five days and to allow them to recover properly before Sunday."